A `2xx2` order matrix will contain `4` elements.<br>
We have to create these matrices using `3` numbers that are `1`,`2` or `3`.<br>
So, total number of all possible matrices are `3^4 = 81`.<br>
Some of the examples of such matrices are,<br>
`[[1,2],[2,3]],[[1,1],[2,2]],[[3,3],[1,1]],`<br>
`[[1,1],[1,1]],[[2,2],[2,2]],[[3,3],[3,3]].`<br>
Similarly, we can create `81` matrices with these three numbers.<br>